Perspective drawing machine



Oct. 19, 1950 o. F. RANDOLPH PERSPECTIVE DRAWING MACHINE SSheets-Sheet-l Filed me s, "1948 I I INVENTOR. oee/zv PANDOLPH,

A T TOE/V5 V5 Oct. 10, 1950 o. F. RANDOLPH PERSPECTIVE DRAWING MACHINE 3 Sheets-Sheet 2 Filed Jun e 8, 1948 FIG. 4.

FIG. 5

my w NP 6 m m 1M m 4 r P 4 F Oct. 10, 1950 o. F. RANDOLPH PERSPECTIVE DRAWING MACHINE I 5 Sheets-Sheet 3 Filed June 8, 1948 JNVENTOR.

oEm v gmvau fl, L BY ATrae/wsvs.

Patented Oct. 10,

UNITED? STATES ATENT OFFICE PERSPECTIVE DRAWING MACHINE Orrin F. Randolph, West? Palm Beam Application June 8, 1941?,Serialhlo. 31,760

two or more related orthographic views of the" object:

Arfurther object of the invention is to eliminatethe necessity for auxiliary construction lines onthe perspective drawings.

It is likewise anobjec't to provide an apparatus of the indicated. character which may be operated quickly and accurately by a person relatively unskilledin the art-of'p'erspe'ctive drawing, the operation resulting in a mimmum: of mental fatigue for: theo'p'erato'r. I

It is also an object to 'pr ovide' an app'aratu' s of the indicated character which is adapted'to be mountedon a drawing board over the drawing paper so as to permit the use of any size drawing sheet. I

Still another object'is to provide an apparatus which is simple, efficient; and comparatively inxpensive and which may be divided into' two proceeds. I

i In order to facilitate ready 'comprehension" of:

the inventionand' particularly itsisa'lient features, this invention is illustrated. on the accompanying; drawingsforming part hereof; and in which? Figure l is a perspective view of an apparatus embodyingthe present invention in a, practical form and illustrating thisapparatus in the process of bein used to produce a perspective view;

Figure 2 is aside elevation of the sameapparatus as seen from the far end thereofin- Fig-a ure 1 the invention will appear in further detail as the specification edu ced, perspective: view showing 9 Claims. (01'. 334) a curve frame and a perspective rule assembly associated therewith as being separated from the rest of the apparatus and used alone;

V Figure 4 is a diagram illustrating a method of i producing the curves determiningthe form of the curve frame used in the apparatus;

Figure 5 is a plan view of the curve frame and a stationary board as well as a slidable frame shift-' able against the mentioned board;

Figure 6 is a fragmentary view of the slidable frame in enlarged perspective showing a multiple supporting socket for a sighting scale providing for different positions of the latter;

Figure 7 is an enlarged section of detail illustrating a pin-attaching means for the curve frame of Figure 5, together with a supporting foot for this frame;

Figure 8 is an enlarged side elevation of a peep hole member with its supporting post and base socket mounted upon the stationary frame supporting thecurve-frame, parts being shown partly' in section to disclose the interior construction; Figure 9- is a 'view of the upright or standing board upon which the elevation of the object to' mbe drawnis normally mounted;

Figure 10 is a perspective view of a point-lo-.- cater-square adaptedto cooperate with and he mounted upon the board of Figure 9 and be shiitable across thesurface thereof during use; Figure 11 is a fragmentary view showing the reverse side of the lower portion of the point-lo-- Figure 12 isan enlarged side'elevationof the sighting scale of Figures 1 and 2 indicating" the manner in which it is mounted in one'of the various sockets, of the base or multiple-socket membershown in Figure 6; I

Figure. 13 is another enlar ed viewof the same:

sightingscale as seen from the left in Figure 12'; Figure 14: is an enlarged sectional detail of a pinmounting for attaching the stationary frame or board which supports the peep hole member Figure 1'7 is a fragmentary perspective view of the peep hole member of Figures 1, 2, and 8, illustrating a modification thereof.

It is well known in the various fields of art, and even in the practical art including drawing that perspective views are the most difiicult to produce, and always require the highest skill, which is sometimes not attainable by certain people, and in any event, not too well executed by even those who are skilled. Moreover, when a perspective view is very detailed and perhaps must be quite accurate, the diificulty is greatly increased.

After duly considering this problem, I have found it quite feasible to produce an apparatus which facilitates the production of perspective views which are quite accurate from elevations and plan views of the object to be reproduced in perspective, as will now be set forth,in detail.

Throughout the various views the same reference numerals indicate the same or like parts. The present perspective drawing apparatus, as shown in Figures 1 and 2, primarily includes a stationary board |8 provided with a pair of pin mountings l9, l9 through which a pair of pins 20, extend down into the supporting board or table 2| upon which the entire apparatus is mounted, as best seen in Figure 14, the point 22 of the pin extending into the wood sufficiently to hold the board l8 stationary during operation.

Upon one end of this board is fixed a base socket 23 by means of screws 24, 24 into the tapered hole 25 of which is fitted the lower tapered end 26 of an upwardly-extending tubular post 21. Slidably projecting upward from this post is a rod 28 normally fixed in position within the tubular post 2'! by means of a screw 29, the rod terminating at the upper end thereof in a stud 30 projecting upwardly with a driving fit into the lower portion of a peep hole member 3|. The tapered hole 25, tubular post 21, rod 28, and stud 39 are all concentric and their common axis is perpendicular to the surface of the supporting board or table 2| on which the stationary board I8 is placed. The mentioned peep hole member is rearwardly cylindrical at 32 with a large bore 33 which terminates, at its center line, as close as practicable to the center line or axis of the post 21 and rod 28. A small peep hole 34 is drilled along the center line of peep hole member 3|. From the opposite side a smaller bore 35 is drilled in a short distance with the inner end forming a flaring continuation of the peep hole 34 at 36, the thickness of the material at the lip of the peep hole being as thin as practicable. The construction described places the peep hole 34 directly on the axis line of the tapered hole 25, the tubular post 21, the rod 28, and the stud 39 and this arrangement obviates the necessity of providing a means for rotational indexing of the parts mentioned in order to insure that the peep hole will be in the desired location. The peep hole member 3| is mounted at an angle inclined downwardly in the forward direction, the large deep bore 33 serving as an eye piece which well overshadows the peep hole 34 and avoids stray light from being reflected to the eye when using the apparatus. For this same purpose the peep hole member 3| is constructed of a dark, preferably dull black material, or all surfaces of the bore 33, the peep hole 34, the smaller bore 35, and its inner end 36 are coated or chemically treated to produce a dark finish, preferably dull black.

For the purpose of cooperating with the peep hole member just described, a substantially rec- 4 tangular slidable frame 31 having a straight-edge 38 adapted to engage slidably against the edge 39 of the previously-mentioned board I8 is provided on its remote corner with a multiple-socket member or block 40 rigidly fixed to the frame and provided with a group of tapering sockets 4|, 42, 43, 44 with their axes set at different angles as particularly indicated in Figure 6, and with their centers in line as shown in Figure 5 and all center lines lying in a single plane perpendicular to the supporting board or table 2| upon which the slidable frame 31 is placed. Each socket is adapted individually to receive the lower tapered end 45 of the base 46 of a sighting scale 41 whose effective working edge 48 is aligned with the central axis 49 of the tapered end 45, while the scale is also provided with a series of subdivisions and numerical indicia, as generally indicated at 59, in Figures 1 and 13, for example, for a purpose which will be explained presently. The near edge of slidable frame 31, as shown in Figure 1, is beveled and provided with a scale 5| disposed at an angle of 90 with the edge 39 of board l8.

In order to cooperate with the peep hole member and the sighting scale 4'! just described, an upright mounting board 52 is provided having at one corner thereof a supporting bridge 53 provided with a pair of spaced feet 54, 54 while at the opposite lower corner the board is provided with a single foot 55 which cooperates with feet 54, 54 to support the board in a position at right angles to the-supporting board or table 2| and to allow free movement of the board upon the supporting board or table. The board 52 is constructed so that its upper edge 56 and its lower edge 51 are both parallel to the surface of the supporting board or table. Upon this board is mounted an instrument which may be termed a point-locatin square, generally indicated at 58, consisting of an upper sliding head 59 having a rear retaining flange 60 best seen in Figure 2, while forwardly a depending straight-edge BI is rigidly secured to the head 59 at right angles to the lower edge 62 and provided upon one side with a beveled working edge 63, lengthwise along the edge of which is marked a brightly colored indicator stripe for the purpose of readily identifying the working edge. This stripe, preferably red in color, tapers to a point at the lower end as generally indicated at 64. Upon the lower end of the straight-edge 6| is fixed a rearwardly-projecting retaining hook 65 extending upwardly behind the lower edge 51 of mounting board 52 and together with flange 60 on the upper sliding head 59 serving to retain the straight-edge 6| in working contact with the forward surface of the mounting board. In order to allow removal of the point-locating square 58 from the mounting board and also proper positioning thereof upon the same board, the latter at one end of its lower edge 51 is provided with a clearance recess 6'6, the lower hook 65 being readily passed through the recess after the flange 60 has been engaged on the top edge of the mounting board. When the square 58 is thereupon slid sidewise along the upper edge or top of the mounting board, the hook 65 will engage the lower edge 51 and retain the straight-edge in association with the board. When in position on the mounting board 52, the straight-edge 6| extends down as far as practicable without actually making contact with the supporting board or table 2| on which the mounting board 52 is set. The back edge 6'! of the straight-edge BI is beveled as shown in Figure 11 to allow the straight-edge to ride up over the edge of the Sheet of aper that will be attached t the tas as s w en the a par tu is is use. U the mee i g 99%?? in ome 13 2 3 c m is l ted a ai s ui 6 by whr q 't Su n the board freni a hook or the like upon the wall when not in use. Hotveverjthe board serves for mounting an elevatiomgenerally indicated at @9, of an object to be reproduced in'perspective upon a sheet it 'rnounted on table ZII The, elevation 69 is mounted so that one'axis'cf the drawing lies parallel with the surface of the supporting board or table 2|- Uponthe t al'ole is also mounted a Plan View of the same Object, s indicated n I, this" plan view being made to the. same, scale th evat $9 with t o g u nal d e I2 (which is parallel to one axis'of the'drawing) seased new ang e W th h'e' ed .9 9f board iein'order to provide the proper predetermined relation with the special curvef rarne and perspective rul combination which willbe described next. l u 20 the qnpqs d o board o that carrying the post 21 and the peep hole member 3i is fixed a special curve frame, generally indicated at it, by means of a pair of removable screws 14,15 the "heads of which are countersunk flush with the surface'of the curve frame. This curve frame 13, which represents a long series of various forms and curves that may be used, consists of three curved sides l5, l6 and H, at the corners of which are located supporting feet (8, l8, l8, through which manually-inserted pins l9, 19, i9 extend down int 'tabIe 2| to retain the curve frame, ran ed position and yet space the same upwardly from the table a sufficient distance to provide a clearance for the slidable frame 3 therebeneath, details of one of said feet with the securing pin being shown in enlarged form in Figure 7. It may be mentioned that this particular curve frame i3 is laid out on the as-' sumption. that the view to be produced will be a three-point perspective the. lower' vanishing point of which maybe termed W, the right vanish'ing point of which 'm'ay' be terme v2 a the left vanishing point of which maybe termed V 'I 'helocations of these vanishing points upon the picture plane with, reference to the point 80 rep resenting the axis oi vision may be found by methods'familiar to 'those skilled in "the art of perspective drawing. Required to be known is the angular position of theobjectin relation to the picture plane and the perpendicular distance from the picture plane to the station pointfrom which the object is viewed. Obviously, these factors may be varied within their limits thus producing an infinite, number of combinations upon which a'widevarietyfof practical designs for the curve frame maybe based. Vanishing pointV serves to form a center for an arc determining the curvature of the upper curved side 15, as indicated in Figure 4, while the curves'ltIand 11 are derived fromjthe vanishing pointsQV? and W, as willbe' m die lv ex la ned; f i

A perspective iulglfc'; the curve frame, gen erally indicated at8],,includes afollower mem; her 8} adapted to ride upon the curves l5, 1, and, ll having a pain of follower pegs or studs 83, 83,norma1ly,following,theexterior edge of the curve-v upon which the follower member 82 may be located, while. projecting, transversely across the curve involved tnward the, interior of the, curve frame, 13', is thefintegral; mg 84 beneath h h ablo 85, 5 db a pain-qt prew fifi 86-1 To thebot'to-m of this spacing block is' sec ed a ra l de p e ab a aren and flexible in the nature of plastic, the two edges of which, 88 and 89, taper toward each other sufiiciently so that when the follower 82 is placed with the studs 33, 83 in contact with the top curve 15 of the curve frame it and lines are drawn along each of the edges 88 and 89 with a pen or pencil, and extended, they will converge at the lower vanishing point V as shown by broken lines in Figure 5. As best seen in Figure 1, this sp acing block is of suflicient thickness to space the drawing blade down in actual contact with the sheet intended to receive e p rs ecti e Vi In. rder o, plo the se v a p t ula noted in Figure 4, assuming that point 8i? coin: s d s, with t e is of s n and t at irc 98 defines the limit of the cone of vision about the axis, the layout of the perspective rule 8i includns ess n al the teatime of h studs 83, 8 and the positions of the edges 88 and 89 of drawi s bla e. m y be e elqvedr e pp curve. 75, a suff cient thicknes of material for t ra e, s allowe be o t e n of vision eer s t e by. c rcl 90, a d in mi ar m n allowing for a suilicient thickness of material for the frame at the curve generally indicated at it exteriorly of circle $0, the layout of the perspectiverule'is first located with the drawing blade 8.1, lying so that in use a line drawn with pen or pencil along edge. 8 3 and passing through point would, if, extended, pass through vanishing point V and the studs 33, 8% would lie in contact with the Outside edge of the curve is. Thereafter the perspective rule BI is assumed to be shifted downward alongthe curve. until the upper stud 83 occupies the position formerly occupied 'by the lower stud '83 the drawing blade 8! being located so. that in use a lin drawn with pen or pencil along edge 8 8 would, if extended, pass through vanishing point V With the per spective rule 81 in the position described it is apparent that a new position for the lower stud 83 has been established, and furthermore it will beneted; that this method of locating a new position for the lower studrnay be repeated as often as desired- In similar fashion, it is possible to located a series of new positions for the upper stud 83; by shifting the layout of the perspective ru1e 8 upward along the curve "16 so that the lower stud- 8 3 successively occupies th positions previously abandoned by the upper stud 83, while in each case the drawing blade 87 is located so that in usealine drawn with pen or pencil along edge 88 would, if extended, pass through the vanishing point V l-Iaving thus established a series of stud-positions 83 65 ,83, etc., it is a simple matter tc prcduce the smooth curve '16 tangent to each stud; In similar manner, the opposite curve ll may beformedg as based on the vanishing point V but as the operation is substantially the same asjust described for curve 16, it will p r aps be superfluous to go into the details at this point. There is, however, one feature that should be noted: When the curve 11 is, produced the perspective rule layout is reversed so that edge 89- off-drawing blade ti! is on th top instead of on the bottom as inthe caseof'curve it. Although different edges of the drawing blade 81 are. used the method of constructionremains the same. A

line drawn along edge 89 of the drawing blade.

and extended will pass through the vanishing gint henev r. he, stu s 3 ,are ntact tht arre -t,

The design of the curve frame 13 combinedwith the perspective rule 8| is particularly advantageous because it permits the operator to draw along the top edge of the drawing blade81 regardless of whether the perspective rule 8| is set on the right or on the left curve of curve frame 73 and also because it permits the operator to draw along either edge of the drawing blade 81 when the perspective rule 8| is set on the top curve of the curve frame 13. In addition, the conditions mentioned remain unchanged even if the curve frame 13 is turned over, reversing it right for left, as is possible when it is used alone as shown in Figure 3.

While a three-sided convexly curved frame is described, I do not wish to be limited to such form of curve frame nor to the exact curvature of the two curves l6 and 11, nor the upper curve 15, but may use other methods and other distances for plotting the curves and may also make the two curves 16 and 1'! symmetrical if I so desire. In particular, I wish to include the possibility of employing a convexly-curved frame (not shown) consisting of three curves, each of which would be formed as an are having a vanishing point as its center. This curve frame would be provided with supporting feet and mounting pins similar to those described hereinbefore. To be used in conjunction with the curve frame, I would provide a perspective rule similar to the one described hereinbefore, except that the drawing blade, instead of being symmetrical around the longitudinal axis of the rule, would be offset to one side sufficiently to bring one edge of the blade in line with said axis, and except that the integral lug and the spacing block on the follower member of the rule would be offset sufficiently to accommodate the drawing blade in its offset position. In addition, while the curve frame has been illustrated as made from sheet material, it is equally within the scope of my invention that it may be stamped out, die cast, formed from rods or sec tions bent to shape and joined together, or fabri cated in any other way mechanically equivalent to the constructiondescribed. Thus, the curve frame I3 represents a series of different curve frames that may be used, the particular one shown and described being merely a good example which serves the present purpose.

Proceeding now to the operation of the device to produce a perspective view from the elevation 69 and the plan view H, it may be mentioned in passing that the slidable frame 31 perferably has the open area 9| to lighten the structure and facilitate shifting the frame by using a minimum of material for the latter. Assuming that the plan View H is mounted as already mentioned, with its longitudinal near edge 12 disposed at an angle of 60 with the far longitudinal edge 92 of frame 3'! which is parallel to the edges 38 and 39 of the frame and of the board l8, respectively,

and also assuming that the elevation 69 is mountt urally be a three-point perspective. In order to line up the views properly in preparation for transfer of the elevation and plan views to the perspective sheet 70, the slidable frame 31 is first shifted to the position shown in Figure 5. In this position point-80, representing the axis of vision on the perspective drawing, lies at the edge of scale 5| adjacent to graduation 4. Also in Figure 5 it will be noted that a center line 93 drawn through the central axes of the socket holes 4| to and also through the central axis of the socket hole 25 forms an angle of with the edge, 39 of board l8. The plan view 1| is placed so that the center line 93 passes through the part of the plan view desired to be shown at the center of the perspective drawing. The plan View is set back from edge 92 of sliding frame 31 sufiicientlyto permit the mounting board 52 and the point-locating square 58 to clear the sighting scale 4'! during the operation. The elevation view 69 is placed on the mounting board 52 at such a height that when the point-locating square 58 is alignedwith the point on the elevation view 69 which will be represented at the center of the perspective drawing and simultaneously aligned at its lower end" upon the point on the plan view H which will be represented at the center of the perspective drawing, then the axis of vision 94 shown in Figure 2 will approximately intersect the mentioned point on the elevation view. It will be noted that the axis of vision is at right angles to the working edge 48 of the sighting scale 41. The operation may be started by singling out the apex of the elevation view 69 mounted on board 52, and then the point-locating square 58 may be slid along the upper edge of the board 52 until beveled edge 63 of straightedge 6| exactly coincides with the apex 95. Then the entire board 52 with the straight-edge 6| in place as described is shifted sufiiciently to locate the lower end of the edge 63 directly upon the apex 96 of the plan View The point 95 on the elevation 69 and the point 96 on the plan both indicate the same point on the object, this point being represented by the present position of point 95 in space.

The operator now sights through the peep hole 34 of peep hole member 3| at point 95 on the elevation 69 and shifts the slidable frame 31 along edge 39 of stationary board I8 until working edge 48 of the sighting scale 41 aligns with point 95 on theelevation 69, the line of sight 91 passing by the scale 41 at point 98. While the slidable frame 31 is in this position, the operator mentally notes the scalev reading at point 98 on the sighting scale 41, transfers this reading to the corresponding scale 5| on slidable frame 31 and places a pencil dot on the perspective drawing at this point as indicated at 99. In similar manner, any desired point defined on the elevation and plan views may be transferred to the perspective drawing. The curve frame 13 and the perspective rule 8| are used in combination to draw all lines which, if extended, would pass through the vanishing points. Either edge 88 or edge 89 of drawing blade 81 may be used to draw the lines which vanish at the lower vanishing point V but the top edge,'whether it be edge 88 or'edge 89, is usedtodraw all lines which vanish at vanishing point V or vanishing point V For example, assuming point I00 has been located on the perspective drawing and it is desired to draw line IUD-It'll, the perspective rule 8| is placed on the curve 15 of curve frame 13 in such a way that studs 83, 83 make contact with the edge of the curve and edge 88 (or edge 89) of the drawing blade 81 aligns with the point I00. The line |08-|0| may then be drawn along the edge of the drawing blade. Again, assuming point I00 is located and line |90|02 was desired, the perspective rule 8| would be placed on curve 16 of curve frame'l3" and the line HID-402 drawn along the top edge (in this case edge 88) of drawing blade 81. Finally, assuming point I was located and line |00--|03 was desired, the perspective rule 8| would be placed on curve 11 and the linev ||l0'-|03 drawn along the top edge (in this case edge 89) of drawing blade 81-. The other perspective-lines for completing the view areascertainedi by means similar to .those just described. The angular lines, such as line 99-404, are, of course, drawn without reference to. the curve frame.

The method outlined is thatwhich is followed for drawing any object in perspective 'so long as an elevation and a plan view thereof on the same scale are simultaneously used. Upon occasion it may facilitate the execution of the perspective viewf'to have two elevations of the object, one a side elevation, and the other an end elevation, mounted upon opposite sides of the.- mounting board 52. If it is then desired to employ the view on the reverse side of the board,

it is merely necessary to remove the pointlocating: square, reverse the board, and replace the square on the forward side. The only point which requires 'to be carefully observed in order to obtain an accurate result is that the, two views be mountedat the same level.

Itmay upon occasion be desirable to use the: curve frame 13 combined with the perspective rule 8! without employing the other parts of the apparatus, and hence, by removing screws 14, 14 this frame is released from board l8 and the pins l3, l9, 19 ma be inserted in feet 18,18, 18 to anchor the frame to the supporting board or table 2|. The perspective rule 8| may then be used on the curve frame l3 to draw all lines which, if extended, would pass through the vanishing points. The operator must judge the length of these lines by eye, the perspective being then, of course, similar to that'produced while using the entire apparatus already described, exceotfor inaccuracies of judgment on the part of the operator. When the curve frame p i3 is used alone this way it is possible to -'turn a over ri ht for left inasmuch as the fe'et"'|8,

1'8, 18. extend upwardly above theframe as far as. they do below it, and it may then be used to draw a 60 by perspective instead of a 30? by 60 perspective.

The remainder of the apparatus, exclusive of the curve frame 13 and the perspective rule 8|, -may also beusedalone to produce a pers ective d awing; In this case the various points are plotted on the perspective view and connected together by lines with the aid ofa straight-edge or drafting curve'as requiredJ Wh en used in this way, it is obvious that the plan View may be set'at any angle of position and that the axis of vision 94 may be directed at ,any angle 'of slant within the adjustable range of the apparatus. This is possible because the. removal of the curve "frame 13 and the perspective rule 8| obviat s the necessity of conforming to the conditions imposed thereby.

It is possible to draw an actual objectwith the apparatus by removing the mounting board to be set onthe table, then the-machine must be placed so that the table will not obscur the extended cone of Vision.

It will be observed that a two-point perspective may be produced by mounting the plan View at. an angle with edge 92 of the slidable frame 31, inserting the sighting scale 4'! in the tapered hole 44 of the multiple-socket block 40 (thus placing it in a, vertical position) and adjusting the'peephole member 3| so that the axis of vision 84 lies horizontal. Of course, if a two-point perspective is to be produced, the curve frame 13 and perspective rule 8| can again be-used when their design has been altered accordingly. If it is desired to draw acnepoint perspective, (the. plan View must be mounted with one of its axes parallel to edge 92 of slidableirarne 31, while the adjustment of sighting scale 41 and peep hole member 3| remain the same as described for two-point per spective. Again the' curve frame 13 and perspective rule 8| can also be used when their designs have been varied to suit this purpose.

While Lhave shown and described the post 21 and the upper supporting rod 28 of peep hole member 3| as forming an extensible unit so as to raise'the peep hole member 3|. by loosening set screw 29; it is evident that this post could be rigid and noheextensible ifso desired. Furthermore, the base 23, instead of being affixed to the board l8 by means of screws 24, 24, could also be integral with the stationary board l8 if the. latter is made of plastic, die cast metal, or similar material, and I reserve the rights to such formsof the invention. It is likewise within the purview of my invention to have the upper portion of the post 28, whether the post be rigid or extensible as described, formed with a yoke I05 with pivots H16, H16 (one shown) for supporting an adjustable peep hole member H11, the pivots being naturally aligned through the peep hole'within peep hole member ID! in order that the peep hole will not be disturbed in positionupon adjusting: member ID! so that it will line up with the desired axis of. vision. The

post illtsupporting the yoke I05 may either be riveted or brazed theretoor made integral with the yoke [05. Returning now to the apparatus shown in Figures l and 2,: the removal of anchor pins 2|], 20 from members l9, I9 on board is and pins 19,

19, 19 from feet I8, l8, m on curve frame ;'|3 frees the stationary board I8 and the curve frame 13 from the supporting board or table 2l, while removal ofpost27| from base 23 allows the stationary board It with its attached curve frame 13 to-be stored away in' flat condition or hung upon a peg on the wall. In similar fashion, the

removal of scale 41 from multiple-socket member 4|] will allow frame 3? to be stored away or hung upon the wall together with theboard l8,

post 2?, rod 28, and peephole member 3|, and also scale 41, and likewise rule 8| and pins 20,20, .and -l-H, 19,19, stored in-abox or receptacle intended for this purpose.

While I'have already suggested certain modifications which are possible, it is manifest that 11 parts and features may thus be modified or used without others within the scope of the appended i claims.

" Having now fully described my invention, I

claim:

1. A perspective drawing apparatus including movable supporting means for supporting an elevation of the object to be drawn in one position,

Stationary means for supporting a plan view of the same object in another position, stationary adjustable sighting means for viewing the elevation; means for locating each given point upon said elevation directlyover the corresponding points-"upon theplan view in succession, a shiftable member having a sighting scale projecting transversely to the 'line of sight from the stationary sighting means, and a second scale fixed upon the shiftable member adjacent to the site of the proposed "perspective view to be drawn, the sighting scale and'the second scale having points upon the plan view in succession, a shiftable member having a sighting scale projecting transversely to the line of sight'from the stationary sighting means, a second scale fixed upon the 'shiftableinernber adjacent to the site of the proposed perspective view to be drawn, the sighting scale and the second scale having mutually corresponding indicia, and guide means for drawing lines from and/or between the points ascertained adjacent to said second scale corresponding to the points of-said elevation sighted 'upon'thesighting scale in various shifted positions of said shiftable member, said guide means including'an open frame which; is stationary with referenceto' the stationary sighting 'i'neans and consists of three curve 'me'mbers'joined at the ends thereof to form the frame enclosing the imaginary circle defining the field of sight for drawingthe proposed perspective view, and a perspective rule having converging side edges and at one end'having a follower member adapted to slide upon the curve members of the frame with a pair of follower pins adapted to engage against the edge'of the" curve member upon "which the follower member is located.

3; A perspective drawing machine "including a vertically-disposed movable supporting'member for supporting an elevation of the object to be drawn, stationary adjustable sighting means for 'v'iewing the elevation, means for locating each given point upon said elevation in predetermined relation to the corresponding points in successionupon-a stationary planview of said object when occupying a "position beneath said vertically-disposed supporting member and the elevation mounted thereon, a shiftable member having a forwardly-inclined sighting scale projectin transversely to the line of sight extending from the stationarysighting means to said elevation, and a second scale fixed upon the shiftable member adjacent to the site of the proposed. perspective view to be drawn, the sighting scale and the second scale having mutually-corresponding indicia'i 4. A perspective drawing apparatus including a shiftable upright support for supporting an ele- 12 vation of the object to be drawn in perspective, adjustable means upon the upright support for individually locating each given point upon the elevation directly over the corresponding points uponra stationary plan view of the same object in succession, a stationary lateral'guide member having an elevated adjustable viewing member mounted thereon for viewing said elevation, a shiftable member having one edge thereof adapted to slide against the stationary lateral guide member and having a projecting sighting scale extending upwardly between said elevation and the viewing member transversely to the line of sight from the latter, a second scale disposed fixedly on the shiftable member at substantially a right angle to the mentioned one edge thereof for determining points upon the proposed perspective view corresponding to the given points viewed at the edge of the sighting scale upon the elevation in shifted positions of said shiftable member, mutually-corresponding indicia upon the sightingscale and the second scale to identify on'the latter the points indicated on said sighting scale, a curve frame having an interior open area fixedly associated with the stationary lateral guide member including a plurality of curved elongated members connected together at the ends thereof to form the curve frame and enclose the imaginary circle defining the perspective drawing field in said open area, and a follower within the latter curve frame ascertained by the indicia upon said second sca1e.-

5. A perspective drawing apparatus including an upright shiftable mounting board to be arranged upon a table or the like for supporting an elevationmounted thereon of the object to be drawn in perspective, a pendent straight-edge having a supporting head 'slidably mounted upon the upper edge of the mounting board, the pendent straight-edge having a working edge for indicating given points upon theielevation upon said mounting board, the latter being shiftable to direct-the lowerend of theworkingedge of the pendent straight-edge directly upon the corresponding points in succession upon a stationary planview of the same object supported by the table, a stationary supporting board mounted upon the table and having a'lateral guiding edge and a post mounted upon one end thereof carrying an adjustable viewing-member, acurve frame member secured upon the other end of the supporting board and having an interior open area defining a working space for drawingthe proposed perspective view, supporting feet for spacing the curve frame upward from the table supporting it, removable means'for retaining the supporting board and curve frame member stationary on said table, a slidable frame guided in movement upon said table against the lateral guiding edge on said supporting board, an I upwardly-directed inclined viewing scale projecting from one portion of the slidable frame transversely to the line of sight extending from the viewing member to said elevation, a second scale fixed upon another portion of the slidable frame adjacent to the curve frame and disposed at a right angle to said lateral guidslidable frame, and a perspective rule in said working space having two drawing edges inclined with respect to the central longitudinal axis of said rule for drawing lines from and/or between the points ascertained in said working-space adjacent to said second scale, and a follower'portion secured to said perspectiverule for engaging upon the curved portions of said frame member.

6. A perspective drawing apparatus including an upright shiftable mounting'board for supporting an elevation mounted thereon of the object to be drawn in perspective, supporting feet at the lower corners of the mounting board for spacing the lower edge thereof from the table supporting it, the mounting board having both upper and lower edges parallel "to the supporting table, a pendent straight-edge having a supporting head slidably mounted upon the upper edge of the mounting-board, the pendent straight-edge having a beveled-working edge for alignment with given points upon the elevation mounted on said mounting board, the latter being shiftable to direct the lower endof" the working" edge of the pendent straight-edge directly upon corresponding points in succession on a stationary plan view of the same object, the plan view being mounted upon the supporting table, a retaining flange upon the supporting head and a retaining hook near the lower end of said pendentstraight-edge for engaging with theupper and lower-edges of said mounting board respectively tdhold the straightedge' against the latter alongits entire length, the lower edge of said mounting board having a clearance recess at one-endfor releasing the retaining hook of said straight-edge andthereby releasing the latter from the-board, a stationary supporting board having'alateral guiding-edge and a post detachably mounted upon one end thereof carrying an adjustable viewing member with the line of sight thereof inclined downward toward an intermediate portion of the elevation on the mounting board, a curve frame member including three elongated convexly-curved members secured together at the ends thereof to form a three-sided frame secured upon the other end of the supporting board and having an intermediate open area defining a working space for drawing the proposed perspective view, supporting feet for spacing the curve frame upward from the table supporting-it, removable means including anchoring pins for retaining the supporting board and curve frame stationary on" said table,

a slidable rectangular frame guided in movement upon said table against the lateral guiding edge on said supporting board, an upwardly-directed inclined and detachably mountedviewing scale projecting from one end of the slidable frame transversely to the line of sight from the viewing member toward said elevation, a second scale.

positions of said shiftable frame, and a perspective rule in said working space having two drawing-edges inclined with respect to the central longitudinal axis of said rule for drawing lines from and/or between the points ascertained in said working space'adjacent to said second scale, anda follower portion secured to said perspective rule at one end thereof for engaging upon the curved portions of said frame member in order to guide said rule into proper drawing positions.

7. A"persp'ective drawing machine including a shiftable upright support for supporting an elevation of the object to be drawn in perspective, a pendent locating straight-edge shiftable upon the upright support for individually locating each given point upon the elevation directly over the corresponding points in succession upon a stationary plan view of the same object, a stationary lateral guide/member having an adjustable elevated viewing member fixed thereon for viewing said elevation, a shiftable member having one edge thereof adapted to slide against the stationary lateral guide member and having a member fixed thereon with a tapered socket, a sighting scale having a tapered lower end fitting said tapered socket and projecting upwardly between the viewing member and said elevation transversely to said line of sight, a working edge on perspectiveview corresponding to the given points viewed at the edge of the sighting scale upon the elevation in shifted positions of the shiftable member; and mutually corresponding indicia upon the sighting scale and the second scale to identify on the latter the points indicated on said sighting. scale. s

8. A perspective drawing machineincluding a shiftable support for suppcrtingan elevation in upright position of an object to be drawn in perspective, a locating straight-edge adjustably mounted on the shiftable support for individually locating each given point on the elevation directly above the corresponding points in succession on a stationary plan view of the same object, a stationary lateral guide member having upon one portion thereof a base with a socket formed therein, an upwardly hollow post having the lower-end fitting detachably in the socket, an upper post member extending adjustably down into the hollow post, means upon the latter for fixing the upper post member at various elevations in said hollow post, a yoke rigid upon the "upper end of the upper post member, a hollow fixed upon the other end of the slidable frame adjacent to the curve frameand disposed at a right angle to said lateral guiding edge on said supporting board, mutually-corresponding indicia upon the inclined viewing scale and the second scale for identifying the points in the working space within said curve frame corresponding to the given points viewed along said inclined viewing scale upon said elevation in various shifted peep hole member having a central peep hole portion therein, the peep hole member being pivotally mounted in said yoke on a horizontal axis passing through said peep hole portion, and the mentioned socket, upwardly hollow post and upper post member being concentric and their common tioned one edge thereof for determining points I upon the proposed perspective view correspond ing to the given points viewed at the edge of the sighting scale upon said elevation in various shifted positions of said shiftable frame, and mutually-corresponding indicia upon the sighting scale and the second scale to identify on the latter the points indicated on said sighting scale.

9. A perspective drawing machine including an upright shiftable mounting board arranged upon a supporting table or the like for supporting an elevation of the object to be drawn in perspective, a pendent straight-edge having a supporting head slidably mounted upon the upper edge of the mounting board, means for holding the straightedge against the latter in various shifted positions thereof along said mounting board, the straight-edge having a beveled working edge for indicating given points upon the elevation mounted on said mounting board, the latter being shiftable to direct the lower end of said beveled Working edge of the pendent straight-edge directly upon the corresponding points in succession upon a stationary plan view of the same object when disposed horizontally on the supporting table adjacent to the lower end of said straight-edge, a detachable stationary board having a lateral guiding edge and a base member having a tapered socket fixed upon one end of the board, an upright post having a tapering lower end detachably fitting into the tapered socket in the base member and upon the upper end having a peep hole viewing member, the central aXis or line of sight thereof inclined downward toward an intermediate portion upon said elevation on said mounting board in a vertical plane disposed at a' enclosing an imaginary circle forming a working field for drawing the perspective view, a movable frame slidable upon the table supporting it against the guiding edge on said stationary board and upon one end having a tapered socket member fixed thereon, a sighting scale having the lower end tapered to fit said tapered socket member and a working edge in line with the central axis of the tapered lower end and socket member and located in a vertical plane at a right angle with said guiding edge of said stationary board, a second scale formed upon the other end of the movable frame and disposed substantially parallel to the vertical plane coinciding with the line of sight or central axis of said peep hole member, the movable frame at the end carrying the second scale being slidable beneath the curve frame, mutually-corresponding indicia on the sighting scale and the second scale for identifying the points in the proposed perspective view in said working field corresponding to the given points viewed along the working edge of said sighting scale upon said elevation in various shifted positions of said movable frame, and a rule movable in said working space for drawing lines from and/or between the points ascertained therein adjacent to said second scale, and guide means fixed on one end of the latter rule engaging with the curved members on said curve frame for guiding said rule into proper perspective positions for drawing said lines.

ORRIN F. RANDOLPH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

